ZYGNEMA 25 



thick, punctate, and markeci by an irregular network of ridges; pits 

 about iM in diameter, 3-6 /a apart. (Pi. II, Fig. 12.) 

 China, Hupeh, Wuchang (H. H. Chung Coll.). 



11. Zygnema sinense Jao 1935. Sinensia. 6, p. 567, PI. i, Fig. 5. 



Vegetative cells 25-27 /i. x 25-48 /i.; conjugation scalariform; spores 

 formed in the enlarged tubes, extending slightly into the gametangia; 

 zygospores subglobose to ovoid, not compressed, 35-42 /x x 40-48 /a; 

 median spore wall brown, pitted; pits 5-8 ^ in diameter, 3-9 /x apart. 

 (PI. Ill, Fig. I.) 



China, Szechwan. 



Differs from Z. lawtonianum Taft in larger zygospores, larger pits, and 

 absence of distinct suture; from Z. areolatum Transeau in having a single 

 median spore wall, larger pits, and smaller vegetative cells. 



12. Zygnema globosum Czurda 1932. Susswasserfiora Mitteleu- 



ropa. 9, p. 109, Fig. no. 



Vegetative cells 26-28^11 x 70-95 ju.; conjugation scalariform; zygo- 

 spores formed in the conjugating tubes, globose or ovoid, 45-50 m x 

 50-65 /x; median spore wall brown, thick, pitted; pits about 3/^^ in diam- 

 eter according to the figure. (PI. Ill, Figs. 2-3.) 



Bohemia; Central India. 



13. Zygnema adpectinatum Transeau 1934. Trans. Amer. Micros. 



Soc. 53, p. 209, PI. 17, Fig. 6. 



Vegetative cells 25-30 /^ x 30-1 00 ju,; conjugation scalariform; zygo- 

 spores formed in the conjugating tubes, ovoid to globose, 36-40 /x x 

 40-50 /a; median spore wall yellow-brown, scrobiculate; pits 2/^ in diam- 

 eter. (PI. Ill, Fig. 4.) 



United States: Illinois. 



14. Zygnema pseudopectinatum Czurda 1932. Susswasserfiora 



Mitteleuropa. 9, p. 115, Fig. 117. Fritsch and Stephens. 

 Trans. Roy. Soc. S. Africa. 9, p. 53. 1921. 

 Vegetative cells 27-30 /a x 50-74 /a; conjugation scalariform and 

 lateral; zygospores formed in the conjugating tubes, globose to ovoid, 

 33-36 /x X 40M; median spore wall brown, thick, reticulate. 

 South Africa, Transkei. 



15. Zygnema areolatum Taft & Transeau 1934. Trans. Amer. 



Micros. Soc. 53, p. 210, PI. 17, Fig. 8. 



Vegetative cells 27-30 m x 46-66 /x; conjugation scalariform; zygo- 

 spores formed in the conjugating tubes, globose to ovoid, 32-46^ x 

 33-50 ju; median spore wall brown, of 2 layers, of which the outer is 



